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Biomedical subjects

K Izawa

Publications and source records attributed to K Izawa.

At least 55 records · Page 3Linked to original sources
PubMed1995

The application of Diapason spinal fixator device: a comparison with the Steffee VSP plate.

Twenty-five consecutive patients who had a variety of lumbar disorders and who underwent lumbar spinal fusion using the Diapason fixator were followed for a mean period of 20 months. The operations included 16 posterior lumbar interbody fusion (PLIF), 7 posterolateral fusion (PLF), and 2 combined PLIF and PLF (PLIF/PLF). As a control group, 38 patients undergoing PLIF using a Steffee VSP plate (VSP) were followed for a mean period of 24 months. There were no significant differences between the two groups regarding the operation time, blood loss, and improvement of preoperative symptoms. However, incidence of incomplete bony union and radiolucent zone around the screws were higher in the Diapason group than in the VSP group. Our study suggests that there was a possibility of insufficient rigidity of screw-rod fixation in the Diapason system.

Adult↗
PubMed1994

The surgical technique of retroperitoneal lavage for the treatment of extended necrotizing pancreatitis.

For cases of extended necrotizing pancreatitis which involve the spread of infectious or hemorrhagic necrotic lesions to the retroperitoneal tissue, we recommend sequestrectomy and subsequent retroperitoneal lavage via the retroperitoneal access. For successful retroperitoneal lavage, as much liquefactive infectious necrotic tissue as possible should be removed from the retroperitoneal cavity during the operation. In addition, the necrotic cavity should be opened, adequately washed out, and catheters placed in the retroperitoneal cavity by retroperitoneal access. Although we have only applied this ideal technique in two patients so far, the details are presented herein. The significance of retroperitoneal lavage lies in the fact that it cleans the retroperitoneal foci of infection and necrosis, and that it eliminates the necrotic material, bacterial deposits, and biologically active substances produced after surgery. Ultimately, wound healing is markedly promoted, leading to improvement in the systemic condition.

Acute Disease↗
PubMed1994

Expression of Kirsten-ras p21 in gastric cancer correlates with tumor progression and is prognostic.

The purpose of this study was to determine the correlation between expression of ras oncoproteins and the tumor stage or outcome of patients with gastric carcinoma. After the specificity of each anti-ras monoclonal antibody was confirmed by protein immunoblot analysis, immunohistochemical assays for a common-ras antigen present in N-, Harvey- and Kirsten (K)-ras oncoproteins, as well as for K-ras specific antigen, were performed on paraffin-embedded carcinoma tissue from 110 patients who underwent curative resection. By Western blot analysis, there was more p21 in fresh cancer specimens than in normal specimens. K-ras expression distinguished advanced from early gastric carcinoma and correlated with depth of cancer invasion. Among the 110 patients, survival rates of those with carcinomas positive for the common-ras or K-ras antigens were significantly lower than of those with antigen-negative carcinomas (p < 0.05). In a multivariate analysis, nodal involvement (p = 0.002), serosal invasion (p = 0.012) and K-ras p21 expression (p = 0.044) were independently predictive of the recurrence. These results suggest that K-ras p21 is a useful marker of tumor progression and poor prognosis after curative resection.

Aged↗
PubMed1994

erbB-2 expression in well-differentiated adenocarcinoma of the stomach predicts shorter survival after curative resection.

BACKGROUND: Correlation between erbB-2 expression, histologic type of gastric carcinoma, and survival after curative resection was evaluated. METHODS: Paraffin-embedded specimens from 120 patients who underwent curative resection of gastric carcinoma were analyzed immunohistochemically for the expression of erbB-2. RESULTS: Enhanced erbB-2 expression correlated with tumor stage and depth of invasion. Well-differentiated adenocarcinomas had a higher incidence of erbB-2 expression than did poorly differentiated carcinomas. Survival rates of 33 patients with erbB-2-positive carcinomas were significantly lower than those of 87 with erbB-2-negative carcinomas (p < 0.001). Survival rates of patients with well-differentiated adenocarcinomas that were erbB-2 positive were significantly lower than those that were erbB-2 negative (p < 0.001). However, the presence of erbB-2 was not associated with altered survival in 46 patients with poorly differentiated carcinomas. Multivariate analysis of all 120 patients revealed that independent predictors of recurrent disease include nodal involvement (p = 0.003) and erbB-2 expression (p = 0.0051). CONCLUSIONS: Our results suggest that erbB-2 expression is a new marker associated with poor prognosis in well-differentiated gastric adenocarcinomas.

Adenocarcinoma↗
PubMed1993

Sphingolipid deficiency induces hypersensitivity of CD14, a glycosyl phosphatidylinositol-anchored protein, to phosphatidylinositol-specific phospholipase C.

Strain SPB-1 is a temperature-sensitive Chinese hamster ovary cell mutant defective in sphingoid base biosynthesis. To examine the effects of sphingolipid deficiency on a glycosyl phosphatidylinositol-anchored protein, we constructed transfectants expressing mouse CD14 from the SPB-1 and the wild type cells. When the cells were precultured in a sphingolipid-deficient medium at 39 degrees C, CD14 expressed in the SPB-1 cells was hypersensitive to phosphatidylinositol-specific phospholipase C (PI-PLC), compared with that in the wild type cells. Moreover, after exposure of the cells to fumonisin B1, an inhibitor of ceramide synthase, CD14, even in the wild type cells, became hypersensitive to PI-PLC. The PI-PLC hypersensitivity in the SPB-1 cells was almost completely suppressed when the cells were cultured in the presence of exogenous sphingosine or sphingomyelin. On the other hand, the hypersensitivity induced by fumonisin B1 was suppressed by exogenous sphingomyelin but not by sphingosine. The suppression by exogenous glucosylceramide was partial under both conditions. Likewise, CD14 molecules in membranes prepared from the sphingolipid-deficient cells were more sensitive to PI-PLC than those from the control cells. These results indicated that a deficiency in cellular complex sphingolipids caused the PI-PLC hypersensitivity of CD14, suggesting the interaction of CD14 with sphingolipids in membranes.

Animals↗
PubMed1993

Extended right lobectomy for Caroli's disease: report of a case and review of hepatectomized cases in Japan.

A 27-year-old man was admitted to Nagasaki University Hospital complaining of fever. Percutaneous transhepatic cholangiography revealed multiple cystic dilatations of the intrahepatic bile ducts of the right lobe, as well as three obvious cystic dilatations and several small dilatations of the intrahepatic bile ducts of the left lobe. An extended right lobectomy was performed. However, the patient later suffered from repeated cholangitis and required the administration of antibiotics as a result of remnant cystic dilatations and stricture of the extrahepatic bile duct following hepatectomy. A slight enlargement of the remnant cystic dilatations, but no new cystic dilatations, were also recognized in the regenerating liver. We reviewed nine cases of hepatectomy for Caroli's disease reported in the Japanese literature, as well as our own case. Among these, four of the seven patients subjected to hepatic resection involving unilateral lobe demonstrated a good recovery. On the other hand, it is difficult to successfully treat Caroli's disease involving both lobes of the liver by hepatic resection.

Adult↗
PubMed1993

Hyperbaric oxygen therapy in the treatment of refractory peripancreatic abscess associated with severe acute pancreatitis.

Five patients with peripancreatic abscesses associated with severe acute pancreatitis were treated by hyperbaric oxygen therapy (HBO). In 3 patients, the course after surgical mobilization of the pancreas and drainage of the pancreas bed was complicated by peripancreatic abscesses. HBO was conducted under a pressure of 2.8 atmospheres for two hours daily. Four of the 5 patients showed a progressive improvement in their condition. In one patient who failed to respond despite seven sessions of HBO, Pseudomonas aeruginosa was isolated from the discharge, and resection of necrotic tissue and drainage were performed. The main effects of HBO were the alleviation of high spiking fever, the improvement of white blood cell count and serum amylase levels, and the reduction of the abscess size. We recognized HBO to be a successful treatment for peripancreatic abscess associated with severe acute pancreatitis and better results were obtained than in cases that did not receive HBO.

Abscess↗
PubMed1992

[Recurrent hepatocellular carcinoma after hepatic resection].

A total of 125 patients with hepatocellular carcinoma (HCC) treated by hepatic resection in our department from 1970 to 1989 were reviewed to determine recurrent factors, recurrent modes of HCC and to assess the treatment for recurrent HCC. Seventy-five of 125 patients had recurrent tumors after the first hepatic resection. The 1-, 2-, and 3-year cumulative recurrent rates after hepatic resection were 25%, 52% and 67% respectively. The size of the tumor, intrahepatic metastasis, portal vein involvement, clinical stage and DNA ploidy pattern were judged as useful predictive factors for recurrence of HCC after hepatic resection. In the patients with intrahepatic metastases, the bilateral lobes of the remnant liver were the most frequent recurrent sites. The treatment for recurrent HCC was divided into 3 groups such as re-resection, transcatheter arterial embolization (TAE) and palliative treatment. The survival curves of patients receiving re-resection and TAE were significant better than those of patients receiving palliative treatment. Patients treated by re-resection for recurrent HCC had the longest survival. The 1-, 3- and 5-year cumulative survival rates after re-resection were 84%, 60% and 48% respectively. It is concluded that the early detection of recurrent HCC is important and re-resection or TAE is effective treatment for recurrent HCC.

Adult↗
PubMed1992

[Evaluation of hepatectomy in small hepatocellular carcinoma--comparison with transcatheter arterial embolization therapy].

Therapeutic effect on 81 hepatectomized patients with hepatocellular carcinoma (HCC) less than 5cm in diameter was compared to that achieved by transcatheter arterial embolization therapy (TAE) in 61. The 5-year cumulative survival rate after hepatectomy was 38%, which was better than that of TAE (8%). Outcome after hepatectomy was better than that after TAE, according to tumor size in less than 2cm in diameter and single nodule. The 3-, and 5-year survival rates for curative hepatectomy were significantly better than those for TAE. But there was no significant difference in survival curves between relative noncurative hepatectomy and TAE. In terms of hepatic reserve with reference to Child's classification, the survival curve for TAE was better than that for relative noncurative hepatectomy in patients with Child-A, but there was no significantly difference between these two methods. Survivors more than 3 years after hepatectomy and TAE were 24 (48.0%) and 11 (23.4%) patients, respectively. Nineteen of 24 patients with hepatectomy had recurrent HCCs, of which reresection was done in 6, TAE in 11 and other treatments in 2. The advantage of hepatectomy in comparison with TAE is a possibility of long-term survival, if curative hepatectomy is performed.

Adolescent↗
PubMed1992

An isolation power supply by phototransmission.

An isolation power supply by phototransmission was proposed, and the conversion efficiency and the electric characteristics of a prototype of the power supply unit were estimated. Infrared light emitting diodes (LEDs) and single-silicon-crystal solar cells were used as light sources and photovoltaic cells, respectively. A maximum conversion efficiency of 3.9% was achieved. The constant output voltage feedback system, which detects the change of the output voltage of the solar cells and controls the driving current of the LEDs, operates this power supply at maximum conversion efficiency independent of loads. The liquid-cooling structure of the power supply unit can keep the conversion efficiency nearly constant independent of the input power. The fabricated power supply has little capacitive leakage current and negligibly small internal noise.

Electric Power Supplies↗
PubMed1991

Tuberculous liver abscess with bronchobiliary and gastrobiliary fistulae--a case report.

A rare case of a primary tuberculous liver abscess with bronchobiliary and gastrobiliary fistula formation is presented herein, emphasizing the difficulty in establishing its diagnosis. The clinical course was complicated and a wide range of antibiotics administered repeatedly, based on the initial diagnosis of a liver abscess, until the final diagnosis of a tuberculous liver abscess was established by histopathological reinvestigation of the resected liver specimen. Thereafter, antituberculous chemotherapy proved extremely effective for the alleviation of symptoms, reduction of the abscess and closure of the fistulae.

Adult↗
PubMed1991

Caroli's disease associated with hepatolithiasis: a case report and review of the Japanese literature.

A 27-year-old woman was admitted to Nagasaki University Hospital complaining of abdominal pain and fever. Percutaneous transhepatic cholangiography showed multiple cystic dilatations of the intrahepatic bile ducts without stone formation. The illness was diagnosed as a pure type of Caroli's disease. No surgical intervention was made. Subsequently, the patient suffered repeated attacks of cholangitis, and six years later, computed tomography demonstrated cystic lesions of both lobes of the liver and stones within the cystic lesions of the right lobe. We collected 62 cases of Caroli's disease reported in the Japanese literature, including our own case. Among them, cholangitis was found in 43.5%, hepatolithiasis in 30.6%, esophageal varices in 17.7% and cholangiocarcinoma in 8.1%. It is difficult to successfully treat Caroli's disease involving both lobes of the liver. Long-term repeated cholangitis could lead to fibrosis of the liver, hepatolithiasis, portal hypertension and cholangiocarcinoma. Considering the above-mentioned aspects of the disease, careful follow-up studies are required in each case.

Adult↗
PubMed1991

[Clinical study on low body temperature in health subjects].

During last year, 931 men aged 51.0 +/- 9.5 years participated in our hospital's 3-day health screening. Their axillary temperature were taken 3 times per day (twice each, at 6:00 a.m., 2:00 p.m. and 6:00 p.m.) during their 3-day stay and the mean axillary temperature was determined for each subject. In 72 among all subjects, the mean axillary temperature was below 36 degrees C. These 72 subjects were classified as low-temperature individuals with normal temperature below 36 degrees C. This study was designed to compare low-temperature subjects with mean axillary temperature, on various factors, such as age, degree of obesity, liver function, renal function, lipids, electrolytes, and biochemical data (blood glucose, serum amylase, and CPK). This study also included seasonal changes in these low-temperature subjects. The following results were obtained. 1) Age was most closely related to low-axillary temperature, and the degree of obesity (modified Broca-Katsura method) had second significant relation. The low-axillary temperature was in common in subjects over 60 years and was also common in obese subjects, regardless of their age. 2) No seasonal effect was observed with low-temperature subjects. 3) Only the age and the degree of obesity (modified Broca-Katsura method) showed negative correlation independently with the mean axillary temperature. (For age, the correlation coefficient was Y = -0.006539X + 36.491, while for obesity it was Y = -0.004536X + 36.203.) Therefore the older and the more obese the subjects, the lower the mean axillary temperature.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Efficient high-performance liquid chromatographic system for protein purification.

An efficient high-performance liquid chromatographic system, consisting of an affinity column and a high-performance size-exclusion column, was developed and applied to the purification of growth hormone receptors from rabbit livers. When a 6-ml sample of Triton X-100 extracts containing 16 mg of protein was applied to the system, 1200-fold purified receptor with a 10% recovery of binding activity from homogenates was obtained within 3-4 h. The purified receptor exhibited one main band on sodium dodecyl sulphate polyacrylamide gel electrophoresis, and the affinity constant (Ka = 6.0.10(9) M-1) was found to be comparable with that of 1% Triton X-100 extract (4.4.10(9) M-1). The injection of 1 ml of 3 M urea solution prior to receptor elution with 10 ml of 6 M urea solution was effective in removing non-specific binding proteins.

Animals↗
PubMed1989

Early carcinoma of the extrahepatic bile duct.

This study attempts to define early carcinoma of the extrahepatic bile duct through a study of 11 patients whose carcinomatous invasion did not extend to the outer layer of the bile duct. The patients were divided into the following 3 groups, namely; a mucosa group comprised of 3 patients, a fibromuscular layer group comprised of 5 patients, and an adventitia group comprised of 3 patients. None of the patients had any lymphnode metastases. Histological characteristics were determined according to infiltrative growth (INF alpha, beta, gamma), lymphatic invasion (ly), venous invasion (v) and perineural invasion (pn). In the mucosa group, INF alpha was observed in 2 patients, while ly, v, and pn factors were all negative. In the fibromuscular layer group, INF beta was seen in 3 patients, ly was positive in 2 patients, while v, and pn factors were negative in all patients. In the adventitia group, INF gamma was found in 2 patients, and ly, v, and pn factors were positive in all patients except for 1 in whom v was negative. Death from recurrence occurred in all the adventitia group patients and in 1 other patient. Early carcinoma of the extrahepatic bile duct could therefore be defined at present, as being carcinoma confined to within the mucosa and fibromuscular layer.

Adenocarcinoma↗
PubMed1989

Development of effective cross-linking method for bioactive substance--enzyme immobilization using glutaraldehyde oligomers.

When a 10% aqueous solution of glutaraldehyde (GA) was alkalized to pH 8.5 in borate buffer solution and heated at 60 degrees C, the ultraviolet spectrum of GA solution showed two distinct absorption maxima. The one at 280 nm with a weak absorbance ascribable to the C = O bond in the aldehyde group shifted to near 300 nm after 50 min with a slight increase in its intensity. Another maximum at 235 nm with a strong absorbance was ascribable to the C = C bond of the alpha,beta-unsaturated aldehyde group which was formed by aldol condensation reaction of GA monomer, and its absorbance increased markedly with increasing reaction time. The high performance liquid chromatography (HPLC) analysis with detection at 235 nm indicated that several GA oligomers were formed by the alkali treatment and their concentrations increased. The cross-linking ability of these oligomers was examined by immobilizing enzymes (alcohol dehydrogenase (ADH), glutamate dehydrogenase (GLDH] to an aminated polymer gel matrix by reaction with the treated GA solution. The enzyme activities increased with increasing concentration of GA oligomers. Then, the GA oligomers were isolated and used as the cross-linking agent. The activities of ADH and GLDH were 4-fold and 13-fold higher, respectively, than those obtained by using untreated GA solution, while the total amounts of immobilized enzymes were almost unchanged. These results suggest that GA oligomers may act as cross-linkers in a manner different from the generally accepted Schiff base formation reaction; a possible mechanism may involve addition reaction of an amino group to the double bond in the aldol condensate of GA.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol Dehydrogenase↗
PubMed1989

[Multimodality treatment of carcinoma of the pancreas].

Although surgical resection has been the mainstream treatment for carcinoma of the pancreas, the operative results have been so disappointing that most surgeons in western countries have given up performing the resectional procedure. On the contrary, Japanese surgeons have never abandoned their dream of surgical treatment as a cure for the disease. Therefore, more and more aggressive procedures have been performed. Our operative results have not so remarkably ameliorated, but we have become knowledgeable on the pathological features of the carcinoma and believe that the best procedure for carcinoma of the head of the pancreas is a pancreatoduodenectomy with extensive dissection of regional lymph nodes and retroperitoneal tissue, and that surgery itself can not cure the disease but multimodality treatment should be established. Two hundred cases with carcinoma of the pancreas in which cystadenocarcinoma and islet cell carcinoma were excluded, were encountered from 1969 to 1987 in our department. Of 200 cases, only 48 cases underwent resection. Resection was divided into curative and non-curative resection according to macroscopic findings and pathohistological examination of the resected specimen. In cases of curative resection group, the average survival period of cases which underwent multimodality treatment was much longer than that without any adjuvant treatment. However, in cases of noncurative resection group, average survival period of cases with multimodality treatment was almost the same as that without adjuvant therapy. Therefore, multimodality treatment should be applied for curatively resected cases in order to obtain better results. Radiation therapy, especially intraoperative radiation therapy is considered to be a promising alternative modality of extensive retroperitoneal dissection. Hepatic metastasis was found postoperatively in about 27 percent of the resected cases. It seems that this type of recurrence occurred by migration of malignant cells from the tumor into the portal vein due to operative manipulation during surgery. Therefore, intraoperative infusion of an anticancer agent through the portal vein is mandatory, and preoperative and postoperative adjuvant chemotherapy should be considered.

Combined Modality Therapy↗